PRESIDENT TRUMP has made his position clear: He would like to see Hillary Clinton investigated. After leading chants of “Lock her up!” during his presidential campaign, Mr. Trump has moved on to tweeting his disappointment over the Justice Department’s failure to look “into all of the dishonesty going on with Crooked Hillary.” These demands for the politically motivated prosecution of Mr. Trump’s former political opponent are profoundly inappropriate and degrading to democracy. The good news is that, so far, the Justice Department appears to be holding firm against the president. But as events this week show, it remains under pressure.

Twice, in July and September, Republican members of the House Judiciary Committee have requested that the Justice Department appoint a special counsel to investigate a host of matters related to Ms. Clinton and former FBI director James B. Comey. On Monday, the department notified committee Chairman Bob Goodlatte (R-Va.) that “senior federal prosecutors” will determine whether the majority’s concerns merit an investigation by the Justice Department or an additional special counsel.

The letter raises questions about political pressure on the department — especially given Mr. Trump’s reported discontent with Attorney General Jeff Sessions’s recusal from the Russia investigation and failure to investigate Ms. Clinton. It’s especially worrying given the absurdity of the matters that committee Republicans would like to see addressed. The lawmakers’ first letter to Mr. Sessions requested an investigation into, variously, Mr. Trump’s evidence-free insistence that President Barack Obama wiretapped him; the debunked conspiracy theory over Ms. Clinton’s supposedly nefarious involvement in the sale of Uranium One in 2010; and Mr. Comey’s alleged leaks to New York Times reporter Michael Schmidt dating back to 1993, when Mr. Schmidt would have been in elementary school. Any credence given by the Justice Department to such a nakedly partisan attempt to kick up dust would be cause for concern.

Mr. Sessions’s appearance Tuesday before the committee should put some of those concerns to rest. Mr. Sessions pushed back against demands for a special counsel to investigate Ms. Clinton, confirming that he intends to abide by Justice Department guidelines requiring a factual basis for initiating an investigation. In this light, the letter to Mr. Goodlatte may be read less as the Justice Department’s caving to political pressure than as a polite rebuff of the House Judiciary Committee’s request.

But Mr. Sessions still should explain how his role in responding to the committee’s request is consistent with his promised recusal from any matters arising from either candidate’s 2016 presidential campaign. He says he will recuse himself later, if appropriate. But why was this matter not immediately handed to Deputy Attorney General Rod J. Rosenstein?

Even if the Justice Department handles this particular inappropriate request appropriately, Mr. Trump shows no intention of letting up his efforts to degrade the democratic cornerstone of independent law enforcement. The latest revelations about his son’s interactions with WikiLeaks remind us why the president might want a change of subject, but the rule of law cannot be perverted in furtherance of political distraction. Testifying before the Judiciary Committee, Mr. Sessions declared his dedication to “maintaining and strengthening the rule of law.” That commitment must remain strong no matter the provocation.